1. Field of the Invention
The present invention is related to a manufacturing method for rectifying diodes. And especially to a method whereby a plurality of upper and lower pins are combined with a plurality of electronic chips and then are systematically processed with plastic etc. by molding for shaping, provided with superficial coarseness, applied with electric conductive material, baked for consolidated combining, and cut into shaped articles. Such rectifying diodes are made by mass production, their process of manufacturing is quick, cost is low, and the volume of each rectifying diode is small, but their effect of electric conduction is good. Thereby, effective area of a circuit board having them can be increased; on the other hand, area needed for the circuit board can be reduced. This meets requirement of small volume electronic articles.
2. Description of the Prior Art
In pursuance of progressing of times and requirements of novelty and variation, articles and utensils are required to be convenient in use and easily carried. Therefore, electronic products are mostly required to be small in volume, convenient for disposing and shipping. Portable electronic products are specially required for volume reducing in order to carry conveniently. Volume reducing of electronic products correspondingly requires small parts for the electric circuits used in the products. While rectifying diodes are essential parts in electronic products, various electronic products need rectifiers to cut out current for rectifying in order to make the electronic products in use stable.
Rectifying diodes used presently (as shown in FIG. 1) are made by punching their electric conductive copper sheets A one by one. A chip B is placed between every two shaped electric conductive copper sheets A, then an insulating layer C is shaped by molding on the two shaped electric conductive copper sheets A. Pin ends D on the two shaped electric conductive copper sheets A are bent to abut on the bottom of the insulating layer C to form a rectifying diode 70.
Such manufacturing mode has quite a lot of defects, by which, rectifying diodes can not meet the desired requirement in manufacturing and use. For example:
1) The diodes 70 must be manufactured one by one rather than by mass production, hence they are time and work consuming; efficiency of work thereof is inferior. PA1 2) When two electric conductive copper sheets A for each diode are applied with an insulating layer C and shaped by molding, volume of the insulating layer C is larger, hence time for molding and drying is longer. PA1 3) The insulating layer C must envelops all the electric conductive copper sheets A and the chip B, the whole volume cannot be reduced, and the volume of the rectifying diode 70 after shaping is large, the area occupied thereby on a circuit board is also large. PA1 4) After the electric conductive copper sheets A are shaped by molding, the pin ends D of the two electric conductive copper sheets A must be bent. While if the left and the right pin ends D are unequally bent during bending process, the left and the right pin ends D of the rectifying diode completed are not even and are subjected to loosening and shaking. When the rectifying diode 70 is mounted on a circuit board in such non well-connected state, current flow will be adversely influenced. PA1 5) When the pin ends D of the two electric conductive copper sheets A are bent, bending force must be moderate in order not to break the pin ends D. Bends of the pin ends D are subjected to crack by stress concentration, thereby the chip B will have small crackles, and life of use thereof will be reduced. PA1 6) When the pin ends D of the two electric conductive copper sheets A are bent, the rectifying diode 70 is subjected to damage by undue bending. Therefore, rate of bad products is increased. PA1 7) Time for manufacturing such a rectifying diode 70 is longer, yet it can not made by mass production; bad products can be given out easily. Manufacturing of such rectifying diodes 70 is bothersome, and cost of manufacturing is higher.
The above stated problems in the known manufacturing mode of rectifying diodes 70 is inevitable, and the rectifying diodes 70 made are inferior in quality, higher in cost, time and work consuming, larger in volume, require larger occupation area on circuit boards and not suitable for small circuit boards. All these problems are expected for solution eagerly.